Mechanical bone-conductive ear



J. PRENN.

MECHANICAL BONE CONDUCTIVE EAR.

APPLICATION FILED APR. 11, 1919.

1,346,72 1 v Patented Jul 13, 1920.

PATENT oFFlcE,

JOSEPH PRENN, OF BOSTON,' MASSACHUSETTS.

MECHANICAL BONE-QONDUCTIVE EAR. I

Application filed April 11,

To all whom it may concern Be it known that I, JOSEPH PRENN, a'citizen of the United States, and resident of Roxbury, Boston, county of Suffolk, Commonwealth of Massachusetts, have invented a Mechanical Bone Conductive Ear, ofwhich the followingdescription, in connection with the accompanying drawings, is a specification, like characters on the drawings representing like parts in each of the several views.

This invention relates toapparatus adapted to provide means whereby persons whose normalsound conducting apparatus is defective either partially or wholly, may hear by means of the transmission of sound vibrations through-bone conduction 'directl to the auditory nerves. The apparatus 0 the invention is specially adapted for use in cases where hearing has been impaired or lost through ailments such as mlddle ear catarrh, chronic adhesive type of catarrh', chronic closure of the Eustachian tube, otosclerosis,

stapes ankylosis,collapes of the cartilaginous meatus, exostosis of the bony canal and other cases where the sound waves cannot be transferred to the auditory nerves through the usual channel of air conduction and the ear drum. The invention is shown as em- '80 bodied ina. mechanical device but it may also be employed'with an electrical e ui ment if desired. A principal object o t e invention is to provide an auditory bone conducting device that is equi )ped'and arranged to amplify the sound vi rations as transmitted to a mouth piece, and to im art them to a surface of the cranium adapte for conducting the vibrations directly to the auditory nerves. The foregoing and other ob-' jects and advantages of. the invention will more frilly appear from the following de--. .tailed description, and the distinctive fea tur'e's of novelty will be.-pointed out in the appended claims.

eferring to the drawings:

Figure l is a side elevation showing a device embodying the invention; A

Fig. 2 is a lengthwise central section thereof;

Fi 3 is a transverse section on line 3- 3 of Fig. 2; and

Fig. 4 is an end view of the device.

The housing of the device consists in a short thimble body 10 in one end of which is threaded a mouth Piece 11, this mouth piece being shown as .this internal thread with an annular shoulder therein whic against the button 18 are transmitted to the 110 ormed with an inner 1919.- Serial No. 289,191.

peripheral flange 11 externally threaded to engage an internal thread at the end of the. body 10. The body 10 is formed adjacent or ledge 12, this ledge being adapted to serve as a rest against which a thin vibratory diaphragm 13 may be fitted. This dia-- phragm is thus held looselyagainst the ledge 12 by screwing up the mouth piece 11 to the required extent leaving a slight play for the vibration of the diaphragm, the diaphragm being shown as en aged at' this peripheral edge by washers of paper or felt 14 interposed at each side thereof. Secured to the ithimble body 10 at one side thereof as seen at 15 is a spiral leaf spring 16 which fills most of the body and carries at its center a stylus pin 17. The stylus pin 17 has a button head 18 which ma be of .rubber or other suitable material a jacent the center of the diaphragm 13 and adapted to be impinged thereby as the diaphragm vibrates to transmit suehvibrations to the spring 17, which is freeand adapted to receive and transmit such vibrations, being held only at its outer end by the screw secured to the body at 15. At the inner end of the body 10 is secured as by threading the same therein a disk cap 19 having a central opening 20 therethrou h. A plate 21 shown as transversely bowe outward is preferably mount-- ed to extend across the central part of this opening, this plate being held to vibrate between light springs 21" mounted in a suitable housin 21 provided therefor in the cap 19. T e plate 21 is shown as having fixed thereto a thin disk21 which may be of mica or the like and extending straight across between the ends of the plate 21 in position to be impingedby the point of the tylus' 17 to receive vibrations therefrom.

us the vibrations of the diaphragm .13

are transmitted through the sty i In use the vibrations of the air from a per- 105 son talkin into the'mouth piece 11 orother sound gat ered thereby are transmitted to the diaphra by the impingement thereof spring 16 and stylus pin 17 and localized by t e special construction and mounting of I us 17 and thence as described through the disk 21 to V the bowed plate 21 fixed thereto which extends across the opening 20 in position to 13 andset' up vibrations said spring and the stylus pin therein. The action of this pin on the plate 21 transmits the vibrations thereto, it being understood that in use the face of the disk plate 19 will be pressed upon the bony surface of the cranium preferably just in front or back of spirit or essential attributes thereof, and I therefore desire the present embodiment to be considered in all respects as illustrative and not restrictive, reference being had to the ap ended claims rather than to the foregoing description to indicate the scope of the invention.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

l. A device of the kind described, comprising a housing body having a mouth piece at one end thereof, a vibratory diaphragm associated with said mouth piece, and a stylus pin adapted to be impinged by said diaphragm, the other end of said body equipped with means energized by said stylus and ada ted to be applied to a .bone conductive sur ace of the cranium.

2. A device of the kind described, comprising a housing body having a mouth piece at one end thereof, a vibratory, diaphragm associated with said mouth piece, and a spiral spring fixed at its outer end to said body, and having mounted for vibration therewith at its center a stylus with a button atone end thereof adapted to be impinged by said diaphragm, the pointed end of said stylus equipped with means to cooperate therewith to transmit vibrations to a bony surface of the cranium for the purpose stated.

' 3. A device of the kind described, comprising a housing body having a mouth piece at one end thereof, a vibratory diaphragm associated with said mouth P1808, a spiral spring fixed at one end of said body and having a stylus carried b its other free end adapted to be impinge by said diaphragm,-

and a means mounted for vibration having an element in position to be impinged by said stylus and ada ted to transmit vibrations to a bony sur ace of the cranium for the purpose stated.

4. A device of the kind described, comprising a housing body having a mouth piece at one end thereof, a vibratory diaphragm adjacent to and in front of said mouth piece, and means mounted and engaged for energization by said diaphragm having an exposed portion of relatively restricted area adapted to transmit localized vibration received by said diaphragm from sound waves of the air to a bony surface of the cranium.

In testimony whereof, I have signed my name to this specification.

JOSEPH PRENN. 

